When we decided to switch from a pop-up to a TT, we first considered HTT's. Like you, we liked the smaller footprint, and the idea of having the tent ends, still gave us that open feeling.
But then reality finally sat in when we remembered what we did not like about having a pop-up in the first place ... rain and cold. With an HTT, if it's raining, you're still closing up shop wet. And for cold weather camping, it's still more challenging to heat.
Granted, they have come a long way with them since 2004, and folks with HTT's have found creative ways to keep them warm and keep water out. For us though, the ease of just parking and going with the extra set-up of tent ends, wet, and cold was enough to steer us to a regular hard sided trailer.
Sometimes, I miss the pop-up, the open outdoor (tent) feeling. But I've never missed the work it takes to set up or take down.
Another consideration was the usability of the trailer while in tow. If you are planning on traveling distances that require overnights on-the-road, you might not always be able to pull the bunk-ends out. Especially with kids, where does everyone sleep?
This was also another reason why we opted for the TT instead of the HTT.
Good luck in your choice. It's your choice, I can only share my reasons why we opted for something else. But there are many happy HTT's owners out there too!
With EVERY RV style, there are positives and negatives. Like I said, one negative of a regular TT is the absence of that open feeling, and lack of wind that can pass through. Trailers just don't provide enough wind-air flow.